LKML Archive on lore.kernel.org
help / color / mirror / Atom feed
From: "Pekka Enberg" <penberg@cs.helsinki.fi>
To: "Andrew Morton" <akpm@linux-foundation.org>
Cc: "Andreas Steinmetz" <ast@domdv.de>,
	"Linux Kernel Mailinglist" <linux-kernel@vger.kernel.org>,
	linux-scsi@vger.kernel.org
Subject: Re: 2.6.20.3: kernel BUG at mm/slab.c:597 try#2
Date: Mon, 19 Mar 2007 10:32:00 +0200	[thread overview]
Message-ID: <84144f020703190132w4596a810k23f3423f36a52630@mail.gmail.com> (raw)
In-Reply-To: <84144f020703190100j5becc9dka2eba58456ab95f3@mail.gmail.com>

On 3/19/07, Pekka Enberg <penberg@cs.helsinki.fi> wrote:
> EIP is at kmem_cache_free+0x29/0x5a
> eax: c1800000   ebx: f0ae12c0   ecx: c18f73c0   edx: c1800000
> esi: c1919de0   edi: 00000000   ebp: 00001000   esp: f1fe7e14
> ds: 007b   es: 007b   ss: 0068
>
> But somehow eax and edx have the same value 0xc1800000 here. Hmm?

Aah, but if you look at contents of the stack:

Stack: f0ae12c0 c1919de0 ffffffea c0137f97 00000000 f0ae12c0 c1919e20 c0168d45
       f0ae12c0 00001000 c0168fb9 c02a77e3 00001000 00000000 00000000 00000000
       00000000 c17bb6e0 00001000 00000000 f1b38be8 00000003 f54ac050 c1b9d6e8
Call Trace:
 [<c0137f97>] mempool_free+0x48/0x4c
 [<c0168d45>] bio_free+0x21/0x2c
 [<c0168fb9>] bio_put+0x22/0x23

You can see that mempool_free is passing a NULL pointer to
kmem_cache_free() which doesn't handle it properly. The NULL pointer
comes from bio_free() where ->bi_io_vec is  NULL because nr_iovecs
passed to bio_alloc_bioset() was zero.

The question is, why is nr_pages zero in scsi_req_map_sg()?

  reply	other threads:[~2007-03-19  8:32 UTC|newest]

Thread overview: 16+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2007-03-19  0:34 Andreas Steinmetz
2007-03-19  6:00 ` Andrew Morton
2007-03-19  8:00   ` Pekka Enberg
2007-03-19  8:32     ` Pekka Enberg [this message]
2007-03-19  8:35       ` Pekka Enberg
2007-03-19 17:49 ` Mike Christie
2007-03-19 18:29   ` James Bottomley
2007-03-19 19:06     ` Mike Christie
2007-03-19 21:12       ` Mike Christie
2007-03-19 23:25         ` Andreas Steinmetz
2007-03-19 23:40           ` Andrew Morton
2007-03-19 23:46             ` Andreas Steinmetz
2007-03-19 23:25       ` Andreas Steinmetz
2007-03-19 21:47     ` Gene Heskett
2007-03-19 22:06       ` James Bottomley
2007-03-19 23:29         ` Gene Heskett

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=84144f020703190132w4596a810k23f3423f36a52630@mail.gmail.com \
    --to=penberg@cs.helsinki.fi \
    --cc=akpm@linux-foundation.org \
    --cc=ast@domdv.de \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-scsi@vger.kernel.org \
    --subject='Re: 2.6.20.3: kernel BUG at mm/slab.c:597 try#2' \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).